Ian Thorpe will be unable to defend his Olympic 400 metres freestyle title in Athens in August after the world record holder was disqualified from the event at the Australian selection trials today.
Thorpe overbalanced on the blocks and fell into the water before the start of his heat on the opening day of the eight-day Australian championships at Sydney's Olympic pool.
In a scene which has already been replayed many times in Australian television news bulletins to a shocked nation, the 21-year-old Thorpe returned to the blocks for his heat but was disqualified.
The crowd gasped in horror as a stunned Thorpe, who was a hot favourite for the 400m freestyle gold at the games, walked away with the colour drained from his face.
An appeal by Thorpe was unsuccessful and the disqualification would stand, Australian Swimming (AS) chief executive Glenn Tasker told a news conference.
Tasker said Thorpe lodged an appeal with the referee but it was dismissed.
Thorpe then went to an AS three-person jury of appeal who viewed television footage of the incident and interviewed Thorpe and event officials.
"Having done that, it is our determination that the referee's decision is correct and a determination of fact, the protest is dismissed, so Ian's disqualification stands," Tasker said.
The policy of the AS allows only the first two finishers at the trials to compete at the Olympics.
Olympic 1,500m freestyle champion Grant Hackett won the 400m final later in Thorpe's absenc.
Hackett said: "It's been a very crazy day. It's been a real shock obviously with Ian.
"It was disappointing not have him there tonight and it's going to be even more disappointing not to have him in Athens.
"But he's got more events to come (100m and 200m) and he's going to show that he is the best in the world in those events."
Thorpe's manager Dave Flaskas said the 200m and 400m world champion, who had hoped to swim the 100, 200 and 400m and three relays in Athens, heard a noise before he fell into the water.
"He is obviously disappointed but I think it is important he gets re-focused on the rest of the meet. He and (coach) Tracey Menzies are regrouping," Flaskas told reporters.